The cooling system is all the year round filled with mix of water, antifreeze and rust-preventing agent. It interferes with a rust and corrosion, adjournment of salts and, besides, increases temperature of boiling of cooling liquid. In the cooling system because of expansion of liquid when heating excessive pressure is created that also leads to temperature increase of boiling of cooling liquid. Pressure is limited to the valve located in a cover of a broad tank which opens with a pressure of 1.4 - 1.6 atm. Faultless functioning of the cooling system of the engine requires the increased temperature of boiling of cooling liquid. At a low temperature of boiling the steam stopper therefore circulation of liquid decreases can be formed and cooling of the engine worsens. Therefore the cooling system all the year round surely has to be filled with mix of water and the listed additives to it.